You can take the Dyson Spheres planet juuuust long enough to grab those resources. You'll need to prepare to defend the stuff though, as when you take the planet the Dyson Gatlings the Sphere spawns will be hostile to you. All the other Gatlings will remain friendly though. Basically what you want to do is bubble up the stuff you want to capture and reinforce the bubbles with engineers just in case, and move in a fleet beefy enough to kill the hostile Gatlings that spawn. I think I had around a dozen to deal with the last time I had to do something like this? Anyway, the instant the station is completed and the facilities switch over, scrap the station. The Dyson will go back to churning out friendlies and you have your new stuff. If you successfully defended the units.